1. Technical Field
The invention relates to an apparatus for measuring the temperature of an object with a temperature sensor which has at least one optical fiber and to a temperature measurement system. The invention also relates a method for producing an apparatus which has at least one temperature sensor with an optical fiber and a temperature measurement system for measuring the temperature of an object, wherein the temperature sensor is placed against the object and connected to the temperature measurement system.
2. Description of the Prior Art
The large number of cables and wires placed underground for different services and the large number of buildings particularly in densely populated areas increasingly call for a determination of the temperatures along a cable run in the ground and a check of the thermal load of the at least one cable. The transmission capacity of an power cable can be optimally utilized if the actual temperature of the cable is known and the thermal limits are simultaneously observed.
EP 0 203 249 B1 describes a power cable which includes at least one optical fiber extending along the cable inside a protective sheath and operating as a temperature sensor. The temperature can be measured with the optical fiber over the entire length of the cable during operation without employing metals. Also, increases in the local temperature and malfunctions can be detected.
Optical fibers can also be used to measure and, if desired, control the temperature of other objects which are at an electric potential, such as the temperature of cables designed for intermediate and high voltages or the temperature of other devices. A fiber length of several meters is required to measure the temperature even of a small object or region with sufficient accuracy. It is not feasible to wind several meters of fiber tightly around the object, if the circumference of object changes with increasing or decreasing temperature.